A bressummer, or breastsummer, in timber-building, is a beam in the outward part of the building, and the middle floors, (not in the garrets or ground floors) into which the girders are framed. In the inner parts of a building, such beams are called "summers".
In addition, breastsummer (but not bressummer) can also be used to describe a dark shade of green. The name of the color comes from the shade of green of the leaves on the trees that were originally used to build bressummers.
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